Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [signal-processing]

the analysis, interpretation and manipulation of signals

Signal processing is an area of systems engineering, electrical engineering and applied mathematics that deals with operations on or analysis of analog as well as digitized signals, representing time-varying or spatially varying physical quantities. Signals of interest can include sound, electromagnetic radiation, images, and sensor readings, for example biological measurements such as electrocardiograms, control system signals, telecommunication transmission signals, and many others. (source)

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Is analog signal arithmetic faster than digital one?

Would it be theoretically possible to speed up modern processors if one would use analog signal arithmetic (at the cost of accuracy and precision) instead of digital FPUs (CPU -> DAC -> analog FPU -> ADC -> CPU)? Is analog signal division possible…
zduny
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How much data could be stored on a standard compact cassette using modern encoding?

My father and I recently dug out his old Commodore 64 from his basement and tried to revive it. Among other accessories, we also found his old Datasette drive, which is essentially a normal tape drive that can be connected to the computer to store…
DLCom
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How is it that two electric currents can travel in opposite directions on the same wire, at the same time, without interfering with each other?

An Introduction to Information Theory: Symbols, Signals and Noise, by John R. Pierce, says the following: While linearity is a truly astonishing property of nature, it is by no means a rare one. All circuits made up of the resistors, capacitors,…
The Pointer
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Difference between bit rate and baud rate and its origins?

Everyone seems to have different definitions everywhere I look. According to my lecturer: \$ R_{bit} = \frac{bits}{time} \$ \$ R_{baud} = \frac{data}{time} \$ According to manufacturers : \$ R_{bit} = \frac{data}{time} \$ \$ R_{baud} =…
Psi
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Writing DSP algorithms directly in C or assembly?

I m working on a DSP project(IIR filtering) on an Analog Devices digital signal processor(BF706) with the compiler suite coming with it, CrossCore Studio. It has some examples for simple DSP stuff like FIR and IIR filters and library functions for…
doubleE
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How do receivers decode multiple GPS signals on the same carrier frequency?

I'm currently researching GPS signals and am trying to fully understand the path of a signal from satellite to receiver. I understand that mixed into the GPS signal is a C/A code as well as a PRN which aids in the process of CDMA that the receiver…
Justanothermatt
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Can I use the FFT to recognize musical notes on a piano?

I want to create a tool which recognizes a few musical notes (I know this is re-inventing the wheel). So I would play middle C, D, and E on a piano and it should be able to classify those notes. Here's how I think I should approach it: Record a…
michaelsnowden
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Why would you put your input amplifier in front of your filtering for an ECG signal?

In this article at eetimes.com they show the signal chain for measuring an ECG. The raw signal of an ECG contains noise and offsets at least a magnitude larger than the real signal. (Some few mV ECG, several tens of mV from power line noise and…
jusaca
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Which one is better as voltage divider: resistive, capacitive , low pass filter,...?

There are different types of voltage attenuators for AC signals ( a short explanation is here). The most well known is a resistive one. Others like capacitive, inductive or low pass filters are available ( Low passes may include many designs…
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Convert analog piezo "transition" to digital signal

I'm trying to get what amounts to a knock indication into a microcontroller input from a piezo sensor. It's looking fairly good now at the fifth iteration, and about ready to provide digital levels for input to a 3v3 MCU. I started with an…
Toby Eggitt
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Why is superheterodyning better than direct conversion?

What is the advantage of having the extra stage of IF, extra local oscillator and extra filtering stage and amplification. It just seems like more work and circuitry. Surely the direct conversion to baseband and the intermediate conversion to…
Lewis Kelsey
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Why isn't the Fourier transform of a single sine wave cycle a single bar?

I have tried different Fourier transform codes out there on single sine waves, and all of them produce a distributed spectrum with a resonance at the signal frequency when they should theoretically display a single bar. The sampling frequency has…
Mister Mystère
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Why can the effective number of bits be a non-integer? What does this physically represent?

The effective number of bits (ENOB) describes the "real" resolution of an ADC. I paid no attention to it when I was first taking the class but now when I think about it I cant really make sense of it that the result can be something like 6.8 bits. I…
Emre Mutlu
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Comparator: Noisy sine to square wave, how much phase noise?

In a circuit a comparator is used to convert a sinusoidal signal to a square wave. The input signal however is not a clean sine wave, but has some noise added to it. The comparator is supposed to be ideal and has a hysteresis which is much larger…
kassiopeia
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Why is a signal that is finite in time domain, infinite in its frequency domain?

Why does every single band-limited signal in frequency have an infinite time domain and vice versa (As it's a symmetric relation, inf in one is finite in the other). I understand how a digital signal with an infinite slope needs infinite amount of…
JustLearning321
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